DSD acid

The product known as DSD acid is chemically identified as 4,4‑Diaminostilbene‑2,2‑disulfonic acid, with the formula C14H14N2O6S2 and a molecular weight of 370.4 g·mol⁻¹. It is supplied by Luoyang Hanyi Chemical Co., Ltd. and carries the CAS number 81‑11‑8. In its dry form the material appears as a light‑yellow powder, while the wet form is a light‑yellow cream; it dissolves readily in ethanol and ether, is insoluble in water, and becomes easily soluble in alkaline solutions. The supplier notes that the acid can be oxidised to a red colour, reflecting its aromatic acid‑amine character.

Typical industry practice for specialty organic acids such as DSD acid is to achieve a purity of at least 99 % and a moisture content below 0.5 %. The quality index reported by the supplier shows a total amino value of 95.0 % and low levels of pigmentation (0.12 %), alkali‑insolubles (0.08 %), benzyl compounds (0.25 %) and ash (2.2 %). These figures are consistent with standard specifications for high‑purity laboratory reagents. Storage is normally recommended at 20‑25 °C in dry conditions to prevent degradation, a guideline that aligns with typical handling of similar sulfonic acids.

The acid is used in the manufacture of dyes, pigments and specialty polymers, and is also employed in research laboratories for coupling reactions. Companies producing colourants, textile chemicals or advanced materials are the main buyers. Luoyang Hanyi Chemical Co., Ltd. does not list a minimum order quantity, price or delivery schedule; prospective importers should contact the supplier to confirm bulk packaging options (25 kg woven bags for dry product or 40 kg woven bags for wet product), Incoterms and payment conditions. The supplier’s Chinese location allows convenient shipment from major ports such as Tianjin or Shanghai.

Luoyang Hanyi Chemical Co., Ltd. is based at Room 505, Block C, Jinyuan International, Taiyuan Road, Jianxi District, Luoyang, Henan, China 471000. The supplier holds a harbor trust tier on the platform, indicating basic verification, but its response rate is recorded as 0 %, with no average response time provided.

The company’s public profile indicates it manufactures and supplies specialty chemicals, including DSD acid, to domestic and international markets. No further details on production capacity, certifications or client references are disclosed, so importers should request additional documentation such as a material safety data sheet and quality certificates when negotiating purchase.